However, “we do not know how extensive methamphetamine consumption was in the Third Reich in an exact quantitative sense; there are indications, but I doubt the suggestions of some that the whole war machine was fueled by these drugs. That’s just not how these drugs work,” said Stephen Snelders, a historian at Utrecht University in the Netherlands who has studied the history of drugs in Nazi Germany.

“I think that the drugs were pragmatically used and administered by (military) physicians and by soldiers and civilian consumers, but the evidence remains scanty for most of the war,” he added.

Now, meth, cocaine and even opiates have been referenced in association with German soldiers in a new book by German author Norman Ohler, “Blitzed: Drugs in the Third Reich,” set to publish in the United States in March, but already released in other parts of the world, including the UK.

“Norman Ohler’s Blitzed depicts the pervasive drug culture that allegedly developed in Germany’s Third Reich,” wrote Paul Weindling, a research professor at Oxford Brookes University, in an article in the journal Nature in October.

“Nazi officials took high-performance drugs such as methamphetamine hydrochloride (crystal meth) and cocaine. German military units and aviators were dosed with the patent methamphetamine-based drug Pervitin (manufactured in Germany from 1937) to improve operational efficiency. And drugs such as Pervitin and metabolic stimulants were tried out on students, military recruits and, eventually, in concentration camps,” Weindling wrote. “Questions remain, however, over precisely how the drugs were tested, prescribed, distributed and used.”

Even though “they’re affecting the same systems in slightly different ways,” meth and cocaine boost the release of two main neurotransmitters in the brain — dopamine and serotonin — which give users a sense of energy and euphoria, said Kristen Keefe, a professor of pharmacology and toxicology at the University of Utah.

Opioids, which also were mentioned in the book, would have provided pain relief, some sense of euphoria and relaxation, Keefe said.

“If you have soldiers out in the field, you don’t want them to feel pain,” she said. “The negative obviously is that opioids readily can kill you if you overdose on them.”

In the United States, methamphetamine is classified as a Schedule II drug, meaning it has a high potential for abuse and is only available through a prescription for medical use that cannot be refilled. Cocaine and opioids are also Schedule II drugs.

Yet such drugs — especially types of amphetamine — have been widely used throughout history in military engagements, Keefe said.

German, English, American and Japanese governments gave their military personnel methamphetamine to enhance endurance and alertness and ward off fatigue during World War II, according to the Methamphetamine and Other Illicit Drug Education project at the University of Arizona.

In 2002, two American fighter pilots accidentally released a bomb that killed four Canadian soldiers in southern Afghanistan. A lawyer for one of the pilots argued that the Air Force pressured the pilots to take amphetamines, also known as “go pills,” which impacted their judgment.

“The pilots were using Dexedrine, or dextroamphetamine, as ‘go pills’ to keep them awake and alert,” Keefe said.

“Historically, it has been used to provide this increase in energy and ability to stay awake in pilots, military pilots … troops,” she said. “So, it’s not a Nazi thing, as much as we might want it to be.”